1. Field of the Invention
The invention relates in general to an optoelectronic measurement method, and more particularly, to a method for measuring optoelectronic characteristics of an organic light emitting diode.
2. Related Art of the Invention
Organic light emitting diode is a kind of flat panel display that converts electricity into optic energy with high conversion efficient. The commonly seen application of organic light emitting diode includes cellular phone, personal digital assistant (PDA), and light sources for various flat panel display. Having the characteristics such as viewing angle independence, simple fabrication process, low cost, high response speed, broad range of application temperature, and full color, the organic light emitting diode meets the requirement of displays in the multi-media era and becomes a popular research topic in industry.
Normally, after an organic light emitting diode is fabricated, temperature, humidity and optoelectronic tests are performed thereon. That is, the organic light emitting diode is disposed in a high temperature, high humidity or high temperature and humidity environment to test the optoelectronic characteristics thereof. The testing method is described as follows.
An organic light emitting diode is disposed in a constant temperature and a constant humidity test machine (such as the machine GTM-225-40-1P). A high temperature, high humidity or high temperature and humidity condition is applied to the constant temperature and humidity test machine. For every period of time (for example, every four hours, eight hours or twenty-four hours), the constant temperature and humidity machine is switched off. The organic light emitting diode is then manually removed from the constant temperature and humidity test machine after the temperature therein is reduced. A power supply for supplying lit-up current of the organic light emitting diode is applied, and optoelectronic measurement equipment (such as SR-2, BM-7 or BM-5) is used to measure the brightness variation of the organic light emitting diode. According to the data of brightness variation manually measured by the optoelectronic measurement equipment, the data are then input to a computer for further process.
With the conventional measurement method, the constant temperature and humidity test machine, the power supply and the optoelectronic measurement equipment are three unrelated apparatuses. Therefore, the organic light emitting diode has to be manually removed from the constant temperature and humidity test machine, and the optoelectronic characteristics thereof are then measured using the optoelectronic measurement equipment. As a result, the high temperature and humidity test is affected to consequently affect the measurement accuracy. Further, as the organic light emitting diode is not removed until the temperature of the constant temperature and humidity test machine is reduced, waiting time for increasing and reducing temperature is consumed. In addition, the conventional measurement equipment requires manually removing the organic light emitting diode from the constant temperature and humidity test machine, manual recording the measurement data, and manually inputting the data into the computer. The conventional measurement equipment is thus very laborious. Further, manually place and remove the organic light emitting diode in and out of the constant temperature and humidity test machine easily injure the operator when improper operation should occur.